Cisco’s Security revenue rose 7% to $2,120 million in the first quarter of fiscal 2027, ended 24 October, according to the results release it filed with the SEC on 12 November as an exhibit to a Form 8-K. In the fourth quarter of fiscal 2026 the category grew 14%, to $2,226 million, so first-quarter Security revenue was about 4.8% lower than the quarter before, by our arithmetic.
Networking revenue grew 43% to $11,132 million in the same quarter, and total productrevenue grew 32% to $14,667 million. Security’s share of productrevenue fell to about 14.5% from about 17.9% a year earlier, by our arithmetic.
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The key insight: As we read the five releases, Cisco’s Security group has not kept pace with the rest of its product line: it grew 7% to $2,120 million while Networking grew 43%, and its share of productrevenue fell to about 14.5% from 17.9% a year earlier, by our arithmetic.
Cisco reports product revenue in four groups: Networking, Security, Collaboration and Observability. Across its last five quarterly releases, Security revenue was $1,980 million in the first quarter of fiscal 2026, down 2% year over year; $2,018 million in the second quarter, down 4%; $2,008 million in the third quarter, with growth of 0%; and $2,226 million in the fourth quarter, up 14%.
For the full 2026 fiscal year, Security revenue was $8,232 million, up 2%, according to the fourth-quarter release. The first quarter of fiscal 2027, at $2,120 million and 7% growth, was the category’s second straight quarter of year-over-year growth in that series, and its growth rate was half the fourth quarter’s, by our arithmetic.
The release lists the 7% figure alongside the other groups: “Product revenue performance reflected growth in Networking up 43%, Security up 7%, Collaboration up 8%, and Observability up 2%.” It gives no further explanation of the Security result.
Year-over-year revenuegrowth of Cisco’s Networking and Security product groups, first quarter of fiscal 2026 to first quarter of fiscal 2027, as reported in Cisco’s quarterly results releases (Form 8-K Exhibit 99.1). Security grew 7% to $2,120 million in the latest quarter; Networking grew 43% to $11,132 million.
Against the Rest of the Portfolio
Product revenue rose $3,590 million from a year earlier, by our arithmetic from the $11,077 million reported for the first quarter of fiscal 2026. Security added $140 million of that, about 3.9%. Networking added $3,364 million and made up about 75.9% of productrevenue in the quarter, up from about 70.1%, by our arithmetic.
Security’s share of productrevenue, by our arithmetic, was about 17.9% a year ago, 17.3% in the second quarter of fiscal 2026, 16.6% in the third quarter and 16.5% in the fourth quarter, before 14.5% in the latest quarter. Collaboration revenue rose 8% to $1,136 million and Observability revenue rose 2% to $279 million, from $274 million a year earlier.
Chuck Robbins, chair and CEO, said in the release that organisations are turning to Cisco for its technology and expertise “to help them scale, secure and optimize their environments for the agentic AI era”. He also said: “We are in the very early stages of a multi-year networking supercycle”.
The WideField Acquisition
The release says: “In the first quarter of fiscal 2027, we closed the acquisition of WideField Security Inc., a privately held security company.” It does not give a price or say how much revenue WideField contributed to the quarter.
The cash flow statement shows $113 million of acquisitions, net of cash and cash equivalents acquired, in the quarter, against $7 million a year earlier. The release does not say whether that line relates only to WideField.
As we read the sequence, the fourth quarter’s 14% growth stands out in a fiscal 2026 that ended with Security revenue of $8,232 million, up 2%: the first three quarters of that year ran between minus 4% and 0%, and the latest quarter, at 7%, sits between those levels.
As we read the mix, Security’s falling share is mainly a story about Networking’s growth: Security revenue was $140 million higher than a year earlier, by our arithmetic, but Networking added $3,364 million, so Security’s share fell even as its revenue rose.
Chuck Robbins, chair and CEO of Cisco, first-quarter fiscal 2027 results release, 12 November 2026
“Organizations are turning to Cisco for our trusted, market-defining technology and our expertise to help them scale, secure and optimize their environments for the agentic AI era.”
Three Implications
FOR THE SECURITY GROUP The release does not explain the slowdown from 14% to 7%; the Form 10-Q and the prepared remarks were not available to us when we wrote.
FOR THE WIDEFIELD DEAL The release discloses the closing but no price; the cash flow statement shows $113 million of acquisitions, net of cash acquired, in the quarter.
FOR THE PRODUCT MIX Networking was about 75.9% of product revenue, up from about 70.1% a year earlier, by our arithmetic; Security, Collaboration and Observability made up the rest.
The Business Engineer Lens
This story maps onto the Business Engineer framework The AI Supercycle.
The framework describes Layer 4, Networking & Protocols, as “The interconnect that turns thousands of GPUs into a single coherent compute fabric.”
As we read it, Cisco’s 43% Networking growth and its raised expectation for AI infrastructure revenue from hyperscalers sit in that layer; Security is not one of the nine layers. The framework predates the results and does not discuss Cisco.
Security revenue as a share of Cisco’s total product revenue, by fiscal quarter, from Cisco’s quarterly results releases (Form 8-K Exhibit 99.1). The shares are our arithmetic.
What Is Not Established
The release does not explain why Security growth slowed from 14% to 7%, report Security orders, or split the category by product. The Form 10-Q was not on EDGAR when we wrote, so its segment notes and risk factors could not be compared. The prepared remarks and slides were not posted when we checked at 21:52 UTC, and we did not hear the earnings call, which began at 21:30 UTC. We did not contact the company.
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Cisco’s Security revenue grew 7% to $2,120 million in the first quarter of fiscal 2027, half the fourth quarter’s 14% rate and about 4.8% below that quarter’s $2,226 million, by our arithmetic. With Networking up 43%, Security fell to about 14.5% of product revenue from 17.9% a year earlier and accounted for about 3.9% of the year’s product revenue increase, by our arithmetic.
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A note on sourcing. All figures come from Cisco’s first-quarter fiscal 2027 results release of 12 November, filed with the SEC as Exhibit 99.1 to a Form 8-K and read in full including the financial tables, and from its four previous quarterly results releases. The Form 10-Q was not on EDGAR when we wrote, and we did not hear the earnings call. Shares, differences and the sequential change are our arithmetic. The company was not contacted for this piece.
Gennaro Cuofano is a CRO and tech executive who has worked in AI since late 2015, starting with bringing NLP, natural-language generation, voice and chatbot products to the marketing industry. His background is in law and finance: he holds a Master's degree in Law and an International MBA with an emphasis on corporate finance (LUISS Business School and the University of San Diego, 2012), and worked as a financial analyst at a real-estate investment firm in San Diego and as an assistant controller. His work focuses on business model strategy, business engineering and, more broadly, structural analysis: how companies make money, read from their own filings. He created FourWeekMBA and leads research there and at The Business Engineer, his newsletter on AI and business strategy, with over 95,000 subscribers and more than 1,000 published analyses. His writing has also appeared on Entrepreneur (for example, How to Digitize a Family Business in Europe) and HackerNoon. Find him on LinkedIn and Substack. See how we source.
